×
Log in to StudySoup
Get Full Access to Introductory Chemistry - 5 Edition - Chapter 8 - Problem 94p
Join StudySoup for FREE
Get Full Access to Introductory Chemistry - 5 Edition - Chapter 8 - Problem 94p

Already have an account? Login here
×
Reset your password

Silicon, which occurs in nature as SiO2, is the material from which most computer chips

Introductory Chemistry | 5th Edition | ISBN: 9780321910295 | Authors: Nivaldo J Tro ISBN: 9780321910295 34

Solution for problem 94P Chapter 8

Introductory Chemistry | 5th Edition

  • Textbook Solutions
  • 2901 Step-by-step solutions solved by professors and subject experts
  • Get 24/7 help from StudySoup virtual teaching assistants
Introductory Chemistry | 5th Edition | ISBN: 9780321910295 | Authors: Nivaldo J Tro

Introductory Chemistry | 5th Edition

4 5 1 271 Reviews
28
0
Problem 94P

PROBLEM 94P

Silicon, which occurs in nature as SiO2, is the material from which most computer chips are made. If SiO2 is heated until it melts into a liquid, it reacts with solid carbon to form liquid silicon and carbon monoxide gas. In an industrial preparation of silicon, 52.8 kg of SiO2 reacts with 25.8 kg of carbon to produce 22.4 kg of silicon. Determine the limiting reactant, theoretical yield, and percent yield for the reaction.

Step-by-Step Solution:
Step 1 of 3

Solution 94P

Balanced equation: SiO2 + 2 C -> Si + 2 CO

1. Find the moles of each:

Grams -> moles

Given kg x 1000 g/1 kg x 1 mol/molar mass

Molar mass SiO2: 60.08 g/mol

Molar mass C: 12.01 g/mol

57.8 kg SiO2 x 1000 g SiO2/1 kg SiO2 x 1 mol SiO2/60.08 g SiO2 = 962.05 mol SiO2

25.8 kg C x 1000 g C/1 kg C x 1 mol C/12.01 g C = 2148.21 mol C

2. Then using the balanced equation, set up a mole ratio: Coefficients/Number of moles.

1 SiO2/962.05 mol SiO2 = 2 C/x

We pretend we don't know the moles of C.

By crossing multiplying, we find x = 1924.1 mol C, which is less than 2148.21 mol C. This tells us we will have EXTRA C, and that SiO2 is our limiting reactant.

We find the theoretical yield by doing a regular stoichiometry problem:

Molar ratio: 1 mol SiO2 : 1 mol Si

Molar mass Si: 28.09 g/mol

57.8 kg SiO2 x (1000 g SiO2/1 g SiO2) x (1 mol SiO2/60.08 g SiO2) x (1 mol Si/1 mol SiO2) x (28.09 g Si/1 mol Si) x 1 kg Si/1000 g Si = 27.024 kg Si

Sig figs... 27.0 kg Si

The percent yield can be found using the following equation:

mass of actual yield/mass of theoretical yield x 100%

Mass of actual yield: 22.4 kg

Mass of theoretical yield: 27.0 kg

22.4/27.0 x 100% = 82.963%

Sig figs... 83.0%

Step 2 of 3

Chapter 8, Problem 94P is Solved
Step 3 of 3

Textbook: Introductory Chemistry
Edition: 5
Author: Nivaldo J Tro
ISBN: 9780321910295

Other solutions

People also purchased

Related chapters

Unlock Textbook Solution

Enter your email below to unlock your verified solution to:

Silicon, which occurs in nature as SiO2, is the material from which most computer chips